Latest 3i-Infotech Aptitude Question SOLUTION: Q. Two trains of equal lengths take 10 seconds and 15 seconds respectively to cross a telegraph post. If the length of each train be 120 metres, in what time (in seconds) will they

Q. Two trains of equal lengths take 10 seconds and 15 seconds respectively to cross a telegraph post. If the length of each train be 120 metres, in what time (in seconds) will they cross each other travelling in opposite direction?

A coffee shop blends 2 kinds of coffee,putting in 2 parts of a 33p. a gm. grade to 1 part of a 24p. a gm.If the mixture is changed to 1 part of the 33p. a gm. to 2 parts of the less expensive grade,how much will the shop save in blending 100 gms.

A.Rs.90 B.Rs.1.00 C.Rs.3.00 D.Rs.8.00

cost of 3 gms of cofee by putting in 2 parts of a 33p. a gm. grade to 1 part of a 24p. a gm = 90 paisa
cost of 1 gms of cofee by putting in 2 parts of a 33p. a gm. grade to 1 part of a 24p. a gm = 30 paisa

cost of 3 gms of mixture changed to 1 part of the 33p. a gm. to 2 parts of the less expensive grade = 81 paisa
cost of 1 gms of mixture changed to 1 part of the 33p. a gm. to 2 parts of the less expensive grade = 27 paisa

There are 200 questions on a 3 hr examination.Among these questions are 50 mathematics problems.It is suggested that twice as much time be spent on each maths problem as for each other question.How many minutes should be spent on mathematics problems

50 ques are of maths so,
150 are remaining..
let x be the time spent on each of other questions...
then 2x is spent on each maths ques...
so, 150*x + 50*2x = 3*60min
250x=180min
x=18/25 mins
but time spent on each maths prb is 2xi.e, 2(18/25 ) mins
total time spent on 50 maths problems is 2* 50 (18 / 25 ) mins
=72 mins..